Adsorption Isotherm of an Insecticide Methomyl onto Natural Clay

Abstract

Adsorption isotherm of an insecticide methomyl onto natural clay has been investigated. The experimental data were fitted to isotherm models, Langmuir, Freundlich and Redlich Peterson. The Langmuir model fit the experimental data significantly better than Freundlich and Redlich Peterson models. A dimensionless separation factor, Ř, was used to judge the favorable adsorption. A chart based on material balance using single batch adsorber was constructed for different percentage of methomyl removal using the Langmuir model where the mass of natural clay required to treat a specified volume of solution is calculated. The effect of temperature showed the exothermic nature of the process. The enthalpy change, ΔH, of adsorption has been evaluated and it has a value of (-17.54 kJ/mol).